The present invention is related to a photodynamic therapy technique useful in the treatment of tumors and their related symptoms.
Lipson et al., J.N.C.I., vol. 26, pp. 1-8 (1961) discussed that fluorescence of human tumors can be accomplished by systemic injection of HpD. Dougherty et al., J.N.C.I, vol. 55, pp. 115-119 (1975) discussed the combination of systemic administration of HpD and exposure to red light emitted by a xenon arc lamp in the treatment of a transplanted murine mammary tumor. Also, Lipson et al., Cancer, vol. 20, pp. 2255-57 (1967) involved the use of intravenous administration of HpD and exposure to filtered light from a xenon arc lamp in the treatment of a human breast tumor.
However, such treatment methods had several disadvantages including:
(1) increased photosensitivity to sunburn resulting from deposition of HpD in the skin;
(2) insufficient accumulation of HpD in large tumors;
(3) poor light transmission through tumors due to clotting and carbonization of blood onto the diffusing surface of the fiberoptic; and
(4) necessity of surgical exposure for deep tumors.